Patent GB-544643-A (GB)
Title: Improvements relating to pressure-responsive devices for valve actuation
IPC: F16K31/126
Filed: 1940-09-19
Abstract: 544,643. Fluid actuated valves. GORDON & CO., Ltd., J., (Hagan Corporation). Sept. 19, 1940, No. 14371. [Class 135] Pressure-responsive valve devices adapted to send out a pressure which is a function of the algebraic sum of actuating pressures, comprises a chamber D connected to a sending line 15, a fixed seating 38 for an inlet valve element 39 controlling admission from a pressure source 48, and a pressure controlled movable seating 41 for an outlet valve element controlling release of pressure from the chamber, the inlet and outlet valve elements being connected together. In operation, on reduction of pressure in the chamber D the outlet seating moves away from the valve means and opens the outlet, on increase of pressure the valve means moves towards the fixed seating and opens the inlet, and both outlet and inlet are closed when the pressure in the chamber reaches a predetermined value. As shown, the valve device comprises four chambers A, B, C, D formed by flexible diaphragms 16, 17, and a fixed partition 3. The diaphragms 16, 17 are rigidly secured together by a rod 18 and tube 26. The seating 41 is formed in the rod 18 and is connected to atmosphere by ducts 42, 45. Flexible bellows 28, 29 seal the chambers B, C from one another. The diaphragms are acted upon by springs 32, 35, the former being adjustable. The valve rod 40 is biased to the left by a spring 46. Pressure fluid is led to the chambers A, B, C by pipes 11, 30, 31. The pressure of the fluid in the chamber D is thus a function of the algebraic sum of the pressures in the chambers A, B, C. In one arrangement a source of pressure is supplied either to the chambers A, B or to A,C so that the pressure in D is either the difference of the pressures in A, B, or the sum of the pressures in A, C, respectively. In a modification the rate of pressure supply to the chamber B is restricted so that a quick response is obtained in the chamber D to any variation in the primary pressure. In another modification chambers A, C are connected to a primary pressure and B is subjected to the pressure in D. In another modification both B and C are subjected to the pressure in D, the rate of delivery in B being restricted. Fig. 8 shows an arrangement in which the pressure in D is utilized for controlling means for regulating pressure or temperature. D is connected through a throttle valve 69 and a volume chamber 71 to the chamber A, B is connected to a constant source of pressure, and C is connected by a pipe 67 to a pressure source. The pipe 67 has a valve controlled by a device responsive to the condition to be regulated by the sending pressure in pipe 15. For example, the valve may be controlled by a thermostat 68 if the pressure in the pipe 15 is used for regulating temperature. Upon variation of temperature from the normal, the thermostat 68 moves the valve to vary the pressure in the chamber C. The pressure in D is thus changed. If such pressure in D persists this is gradually communicated to A so as to be neutralized. Specification 524,077 is referred to.